Hemiacetals



action temperatures of to 80 C. are satisfac- Patented Oct. 27, 1 953 7 V 1 i i ...HEMIACETAL George W. Mast, South Salem,-and Floyd ErAnperson, Yonkers, N. Y., assignors tofNep'era Chemical C01, In'c., Nepera. Park, Yonkers; N. Y.; a corporation of New York 'NdDrawing. Application May 21, 1952, Serial No. 289,216

sclaims. 01. 260-611) This invention-relates tocertainnovelhemiace- 3-methyl-1-pentyne-3-ol tal" compounds 'and"relates more particularly to 2-methyl-3-butyne-2-ol hemiacetals of chloral, i; e."tricl'iloroacetaldehyde. Propa y ol An object of this invention is the production 3-b y of hemiacetals of chloral wherein the alcohol 5 r -m y -p l residue in said hemiacetal structure contains an 3-buty e-1-01 unsaturated, acetylenic carbon to carbon linky -P agg 2-heptyne-1-ol Anotherpbjectof thisirlventionisthe proauc- -ltion of hemiacetals of chloral which exhibit de- Q 'l' 3-octyne-1-ol 2-nonyne-1-o1 3-nonyne-1-o1 3,4-dimethy1-1-pentynel3-ol 3,4-dimethyl-1hexynee3b1 3-isopropyl-4-methyl-l-pentyne ii-ol sirable hypnotic and sedative activity.

Other objects ofthisinvention will appear from the following detailed description.

The novel compounds of our invention may be 1 represented by the following general structural formula: 3-isopropyl-1-hexyne-3-ol OH 9R1 1-nonyne-3-o1 3-methyl-l-nonyne -3-ol Ol3C H 0 (:J (CHz)'? C=C R 1methyl-2-octyne+1!-ol';and

R2 l-methyl-l-ethyl 2-octyne-1-ol wherein n is to 0 to 3Fa3nd'R1' and R3 are As is well known, acetal'formation takes place members of the group consisting of hydrogen and at the carbonyl group of the aldehyde, the reacsaturated alkyl radicals having from 1 to 6 carbon tion resulting not only in the formation of a hyatOm Thus, 'a' p 'ej R ',"R-2,"and fR-a' m y droxy group, but intheformation, as well, of an be e m 0 different and y e a methyl, ether linkage between the carbon atom of the e yl, P y p y vfbllllyl, a y heXyl chloral carbonyl group and-the'carbon-atom to group. In the novel compounds of our invention, I which the hydroxy radical of the acetylenic alco-' R1 and R2, ak n together, m y o comprise the hol is attached, yieldingcompounds of the struccarbon atoms necessary to form a saturated cytural formula given above. These compounds-are cloaliphatic ring. 1 useful therapeutically sinc'e they have desirable The novel compounds of our invention may be hypnotic and sedative action. obtained byt'reacting chloral with a suitable In order further to illustrate our invention,

acetylenical'cohol. -In carrying out the reaction, but W ut beingilimited t tfir' o g it is preferable that anhydrousconditions be a p 'a i maintained during the reaction. Inert solvents such as petroleum ether, hexane or cyclohexane may be employed as a. reaction medium. Re-

Example I 40 105 parts by weight of 3-methyl-1-pentyne-3- 01 and 158 parts by weight of anhydrous chloral tory and the iormation of the hemiacetal 1s usuare dissolved in about 330 parts by weight of y i sg afteg abet? 2 to g a In troleum ether and the solution warmed to a temrymg Du 6 con ensa Ion w ere y our nove perature of 100 C. for about 30 minutes' The rehemiacetals are formed the reactants are pref action mixture is then cooled to a temperature of erably employed in about stoichiqmetric propor' 5 C. for about 48 hours and a white crystalline 1310118. The novel chloral hemiacetals 0f 01.11 inprecipitate of 3 t 1 1 t n 3 1 i Vention are solid, crystalline compounds in tal of chloral is obtained. This novel hemiacetal eral, but some are Oily in naturehas a melting point of 62-62.5 C. The compound To obtain the novel hemiacetals of our inven- 50 has t following l tion, chloral may be reacted with various acetylenic alcohols in the manner described above. As CHB examples of suitable acetylenic alcohols which J may be employed to form said hemiacetals there T may be mentioned: H. 11'

Example II 200 parts by weight of 2-methyl-3-butyn-2-ol and 350 parts by weight of chloral are placed together in a flask in about 525 parts by weight of petroleum ether and the reaction mixture left at room temperature for several hours. The flask is then refrigerated and after standing for about three days, a crystalline product is obtained. The crystals are filtered off, thoroughly washed with petroleum ether and then dried under vacuum. The melting point of the chloral hemiacetal of 2-methyl-3-butyn-2-ol thus obtained is 77-78 C.

The yield is 83% of theory. This compound has the following formula:

CH3 nozo-Js-o-cn-oon Example III HO H Example IV 200 parts by weight of 3-octyn-l-ol and 234 parts by weight of chloral are placed together in 5 25 parts by weight of petroleum ether. A warmingis noted on mixing and the reaction mixture is left at room temperature for several hours. The mixture is then subjected to prolonged cooling at a temperature of 70 C. An oily product is obtained on removal of the petroleum ether. The oily product obtained consists of the chloral hemiacetal of 3-octyne-1- 01 having the formula:

It is to be understood that the foregoing detailed description i given merely by way of illustration and that many variations may be made therein without departing from the spirit of our invention.

l-Iaving described our invention, what we desire to secure by Letters Patent is:

1. The hemiacetals of chloral of the following formula:

OH R; Cher-HO-(CHI)|\CECRI wherein n is to 0 to 3, and R1, R2, and R3 are members of the group consisting of H and alkyl radicals containing from one to six carbon atoms and R1 and R2, taken together, a cycloalkyl ring. 2. The novel hemiacetal of chloral having the formula:

3. The novel hemiacetal of chloral having the formula:

HOEC

4. The novel hemiacetal of chloral having the formula:

CH5 c CH: 11050-6 H:

CH2 .HooH

5. The novel hemiacetal of chloral having the formula:

GEORGE W. MAST. FLOYD E. ANDERSON.

References Cited in the file of this patent Sumerford, Jour. Amer. Chem. Soc., vol. 7 0

(1948), page 448. 

4. THE NOVEL HEMIACETAL OF CHLORAL HAVING THE FORMULA: 